Improvement in sheet-metal boilers



UNITED STATES PATENT OFFICE.

ANDREW ONEILL, OF PORTSMOUTH, OHIO.

IMPROVEMENT IN SHEET-METAL BOILERS.

Specification forming part of Letters Patent N0. 49,546, dated August 22, 1865.

To all whom it may concern:

Be it known that I, ANDREW ONEILL, of Portsmouth, Scioto county,Ohio,have invented a new and useful lmprovem ent in Sheet-Metal Boiling-Vessels; and I do hereby declare the following to be a full, clear, and exact description thereof, reference being had to the accompanying drawings, making part of this specification, and in whichm Figure 1 is a sectional perspective view of a vessel embodying my improvement. Fig.2 is a sectional perspective view of my improved struck bottom. Figa?) is a section of the shoulder and contiguous parts.

A, B, O, D, and E are diagrams illustrating pre-existing devices.

My invention is an improvement upon the customaryboiling-vessel,whosebottom(usually of copper) has a depression or pit7 to enter the stove, and whose body (usually of tinned iron) is united to the bottom in such a manner as to form aseamed or jointed angular shoulder for contact with the stove. (See Diagram A.) Such vessels are well known to suffer rapid and destructive deterioration at the shoulder and lower portion of the bodya `yesult in part of the laying bare of the sheet-iron by the melting of those portions ot the tin in contact with or close proximity to the stove and in part, of the opening and closing of the joint (see Diagrams B and C) by the frequent lifting and setting down of the full vessel, so as to permit the entrance of dirt and moisture to the seam, and the consequent oxidation and giving way of the metal, accompanied by a settling ot' the marginal portion of the bottom, so as to form a gutter orvalley which retains water and other corrodents. (See Diagram G.) These evils are especially observable at those portions of the common oblong wash-boiler where the flat sides join the bottom. Boilers which have thus given out cannot be repaired by cutting away the corroded zone of tin and seaming anew to the bot tom, because the portion of the bottom which has formed part of the old seam cannot be used a second time, and to remove it would make the bottom too small to fit the body. Hence such bottoms can be made available only by attaching a new body of smaller circumference or by covering the corroded parts of the old body with a patch.

The above diculties, so far as they related to the direct contact of tin with the stove, were about fifteen years ago essayed to be overcome by Fenton H. Lawson, of 176 Main street, Ciucinnati, and many others, by providing a copper band or zone whose upper edge was seamed to the body and whose lower edge was seamed rectan gularl y to the bottom in the common way, (see Diagram D 5) but this expedient leftundisturbed the evils attendant on a joint at the an gle, and was otherwise objectionable owing to the serious additional cost and the patched appearance of the vessel. Subsequent operators have constructed buckets by taking a simple flan geless struck-up pan and seaming its raised edge directly to the body, (see Diagram E5) but it is believed that no pitted boiling-vessel of sheet metal has heretofore been constructed otherwise than with a seam or joint at the very angle or shoulder of the vessel.

In the accompanying drawin gs,F is my struck or stamped copper bottom, having a customary pit, G, surrounded by an elevated horizontal portion, H, which differs from the common form in having its outer edge struck upward so as to presentaronnd shoulder, I, and a raised rim, J, having a brim or marginal lip, K, (see Fig. 2,) which being folded and doubled (see Fig. l) becomes a portion of the elevated double-seamed joint K L, which unites my improved bottom to the body M.

One great advantage of removing the seam entirely from the shoulder in boiling-vessels 1s that the cost and labor of soldering and the injurious melting action ofthe soldering-bit upon the tin may be wholly avoided, because the very ductile nature of copper and the very slight strain upon a seam thus situated enable a perfectly tight joint to be made by doubleseaming alone.

Another advantage of my improvement is that tinsmiths may be furnished with copper bottoms stamped perfectly true and of an exact uniform size andpattern, which bottom may be double-seemed directly to their bodies without the labor and wastage incident to scribing and trimming.

My invention is intended more particularly for boiling-vessels having copper bottoms and tin bodies, but may be used advantageously in such vessels when composed of but one material, whether of copper, tin, galvanized iron, or other sheet metal Disolaiming, broadly, the construction of ves- In testimony of which invention I hereunto sels having struck or stamped bottoms and eleset my hand. med seams ANDREW ONEILL.

I claim herein as new and of my invention- A sheet-metal boiling-vessel whose bottom Witnesses: is struck or stamped with a pit77 or drop, GEO. H. KNIGHT, a seamless shoulder, and an elevated margin. J AMES H. LAYMAN. 

